Malware, Viruses and Security Flaws on Macs

Can Macs actually get viruses? Well the short answer is – yes. Although MacOS is more secure, you are still not completely protected.

Contrary to popular belief, Macs are not immune from malware, worms, ransomware and Trojans. It’s certainly true that viruses are not as prolific on Macs as they are on Windows, but this is quickly changing. Viruses are essentially just pieces of malicious software, coding to run on a specific operating system, such as Windows or MacOS. Because Apple hold a far smaller market share of computers than Windows, Mac users have traditionally been protected by “security by minority”. Because the goal of viruses is to infect as many systems as possible, it’s just easier to build them specifically to target Windows machines. Many forms of malware – such as ransomware – as designed to make a profit, so focussing on the operating system with the largest share of the market is a no-brainer for cybercriminals. The WannaCry ransomware in May 2017 only targeted Windows machines, and was no threat to Mac users.

As of February 2019, Apple only had a 9.65% share of operating systems installed on desktops, compared to Windows’ 87.56% share. But Apple’s share of the desktop OS market has increased by more than three times from 2009 to 2017; many individuals and businesses, particularly creatives, are switching to Macs. This explains the rise of viruses targeting Mac desktops over the last few years. Malwarebytes conducted a study earlier this year that found that Mac threats increased by 400% from 2018 to 2019. Because of the widespread myth that Macs are immune from viruses, cybercriminals are targeting the OS specifically in order to take advantage of this complacency.

Since the Oompa-Loompa/Leap worm, delivered over the iChat instant messaging program, first appeared in 2007, there have been several examples of viruses that specifically target Macs. In 2019, the OSX/Linker malware came to light. MacOS uses something called Gatekeeper, which checks all software downloaded from the internet for signs of malware. Applications downloaded from a network, in this instance from an NFS server, are treated differently, and this makes it easier for malware to infect a Mac.

Another Mac malware, OSX/CrescentCore, was able to bypass Gatekeeper’s protections because it had a signed Apple developer certificate. Like many Mac malwares, it was disguised as an Adobe Flash Player DMG file, and after checking the system for antivirus software, it would install unwanted software, typically an app called Advanced Mac Cleaner. This malicious software, like many malwares, purports to be able to detect problems with the user’s machine. In reality, it severely impacts the system’s productivity with junk files, alerts, unneeded login items, and other apps that eat up hard disk space.

Mac users need to understand that they are not immune from viruses. While Windows still dominates the operating system market, cybercriminals are increasingly targeted Macs. You should take steps to avoid becoming a victim of cybercriminals. Make sure your Mac is equipped with up-to-date antivirus software, and be extra careful when installing DMGs that have been downloaded from non-official sources.

Mac Viruses